I stayed at a regular hotel in a small Chinese style room near Sukhumvit Soi 15 and it might be helpful to compare the two.
Kanthima's place:
Positive
Quieter and easier to get to sleep
no ladyboys or bar crowd immediately outside room
Larger room with comfortable desk and chair
Large Refrigerator
Laundry service for only 100 baht
other guests were quieter
plumbing was better
Same
Shower, A/C,
both a block from 7/11, about 5 minute walk to BTS stop
Downsides
No hot water in sink(easy enough to shave in the shower)
Staff didn't speak English quite as well(but Kanthima responded to my questions via airbnb message quickly)
farther from bars and late night food(still just 5-10 minute walk though)
None of the downsides detracted from my trip. I gave 5 stars and would be happy to stay here again.